Agitator construction

ABSTRACT

An agitator includes a high strength, continuous metal axle, a pulley held on one end of the metal axle and a sleeve of lightweight plastic material received over the axle. The agitator is manufactured by molding a pulley body onto an underlying metal support or D-nut, fitting an axle into the pulley, molding a sleeve around the axle and securing a cleaning structure on the sleeve.

This application is a 371 of PCT/US02/11291 filed on Apr. 10, 2002 whichclaims the benefit of U.S. Provisional Patent Application Ser. No.60/282,865 filed Apr. 10, 2001.

TECHNICAL FIELD

This invention relates to vacuum cleaners, extractors and the like and,more particularly, to an agitator for use in such cleaning equipment.

BACKGROUND OF THE INVENTION

Upright vacuum cleaners, extractors and canister vacuum cleaners withpower nozzles incorporating rotary agitators are presently manufacturedand marketed by a number of different companies. The agitators carrycleaning structures such as rubber wipers, beater bars, brushes andtufted bristles to brush or beat dirt and debris from an underlyingsurface such as a carpet being cleaned.

The rotary agitators are rotated quickly at speeds up to 2,500–6,500 rpmand through engagement with the underlying carpet, are subjected tosignificant sheer forces. As such, the agitators must have relativelyhigh inherent strength to withstand operation over an extended servicelife.

The present invention relates to a relatively low profile agitatorconstructed to have the necessary strength to reliably and dependablyfunction over a long service life. Such a low profile agitator may,advantageously, be incorporated into a low profile nozzle assembly of anupright vacuum cleaner, power head or extractor which is capable ofcleaning under overlying obstacles such as the projecting margin ofbuilt-in bathroom and kitchen cabinets or furniture such as beds,dressers and the like.

SUMMARY OF THE INVENTION

In accordance with the purposes of the present invention as describedherein, an improved agitator is provided for use in upright vacuumcleaners, extractors and power nozzles of canister vacuum cleaners orthe like. The agitator includes a high strength, continuous metal axle,a pulley held on one end of the metal axle and a sleeve of lightweightplastic material received over the axle. The sleeve carries a cleaningstructure which may, for example, be selected from a group consisting ofa beater bar, a brush, tufted bristles, a wiper and combinationsthereof.

The sleeve may be cylindrical in shape and have a diameter no greaterthan about 22.00 mm. The axle may have a diameter of between about 4.00mm to about 8.00 mm. In this way the axle acts as a high strengthbackbone for the sleeve while the sleeve has the necessary thickness toreceive and securely hold the cleaning structures. Advantageously, thetotal construction has a low profile thereby allowing installation ineven the most low profile nozzle assemblies, power heads or extractors.

The pulley includes a hub for securing to the axle. The pulley alsoincludes a metal D-nut for engaging a stub shaft of a drive geartypically carried on the nozzle assembly, power head or housing of thevacuum cleaner or extractor to which the agitator is mounted. Stillfurther the pulley includes a pair of projecting box ribs and the sleeveincludes a pair of projecting flanges for receiving and engaging the boxribs. The sleeve also includes a collar and a pair of projecting lugsfor engaging in the pair of box ribs. Together, the hub, projecting boxribs, collar, flanges and lugs provide an interlocking structure forsecurely fixing the pulley on the axle.

In accordance with yet another aspect of the present invention, a methodof manufacturing an agitator is provided. The method includes themolding of a pulley onto a D-nut. This is followed by the step offitting an axle into the pulley. Next is the step of molding a sleevearound the axle. Then comes the step of securing a cleaning structure onthe sleeve.

In the following description there is shown and described one embodimentof the invention, simply by way of illustration of one of the modes bestsuited to carry out the invention. As it will be realized, the inventionis capable of other different embodiments, and its several details arecapable of modification in various, obvious aspects all withoutdeparting from the invention. Accordingly, the drawing and descriptionswill be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWING

The accompanying drawing incorporated in and forming a part of thespecification, illustrates several aspects of the present invention, andtogether with the description serves to explain the principles of theinvention. In the drawing:

FIG. 1 is an exploded perspective view of the agitator of the presentinvention;

FIG. 2 a is a detailed cross-sectional view of the agitator shown inFIG. 1;

FIG. 2 b is a full cross-sectional view of that agitator;

FIG. 3 a is a perspective view of the end of the pulley secured to theaxle of the agitator;

FIG. 3 b is an end elevational view of the pulley shown in FIG. 3 a;

FIG. 3 c is a perspective view of the axle and sleeve;

FIG. 3 d is an end elevational view of the end of the axle and sleeveshown in FIG. 3 b; and

FIG. 4 is a detailed elevational view showing the connection of thepulley on the axle and sleeve.

Reference will now be made in detail to the embodiment of the inventionillustrated in the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION

Reference is now made to the drawing figures and particularly FIGS. 1and 2 showing the agitator 10 of the present invention. The agitator 10generally comprises four component parts, the axle 12, the sleeve 14 onthe axle and the pulley 16 including the metal support, mounting fixtureor D-nut 18.

The axle 12 is a single continuous shaft of high strength metal and mayhave a diameter between about 4.00 to about 8.00 mm. The sleeve 14around the axle 12 is preferably formed from molded plastic such aspolypropylene/ABS or any other appropriate material. The sleeve 14 mayinclude spaced through slots 20 and spaced, axially extending grooves21. The slots 20 allow the axle 12 to be held during the sleeve moldingprocess. The slots 20 and grooves 21 are also of sufficient size anddepth to receive a scissor blade so that one may easily cut hair, stringor other elongated material that might become entangled on and wrappedaround the agitator 10. Thus, these slots 20 and grooves 21 greatlysimplify the cleaning process.

The sleeve 14 is cylindrical in overall shape and has a diameter nogreater than about 22 mm. As a result, the agitator 10 may be utilizedin very low profile vacuum cleaners that provide the necessary clearancefor cleaning under low overhangs such as furniture and kitchen andbathroom cabinet margins. The high strength metal axle 12 providesrigidity, strength and balance or TIR to the agitator 10 yet therelatively small diameter of the axle advantageously allows the agitatorto be made with a small diameter or low overall profile as described.

As illustrated, the sleeve 14 includes two helical patterns of tuftedbristles 22 which function as cleaning structures for brushing andbeating the nap of a carpet as the agitator 10 is rotated at rpms up to2,500–6,500 by the cleaning equipment (e.g. vacuum cleaner, power head,extractor) to which it is operatively mounted. More particularly, aseries of holes are drilled in the sleeve 14 and the tufted bristles 22are secured in those holes with an appropriate adhesive or by mechanicalfastening means such as staples.

The pulley 16 may be formed from nylon or other appropriate material andis molded on the D-nut 18. The D-nut 18 is preferably formed from a highstrength material such as sintered powder metal. The D-nut 18 includesan oblong socket 24 that is sized and shaped to receive a stub shaft(not shown) of an appropriate drive gear which is held for relativerotation on the cleaning equipment to which the agitator is mounted.

As best shown with reference to FIGS. 3 a, 3 b and 4, the molded portionof the pulley 16 includes a hub 26 and a pair of projecting box ribs 28,30: the two box ribs extending in opposing radial directions from thehub. As best shown in FIGS. 3 c, 3 d and 4, the sleeve 14 includes apair of projecting, arcuate flanges 32, 34 and a pair of projecting lugs36, 38 with the flanges and lugs alternating around the axle 12. Anannular gap 40 is provided between axle 12 and each of the flanges 32,34 as well as each of the lugs 36, 38. The pulley 16, including the beltreceiving channel 17, is secured to the axle 12 by pressing the twoparts together so that (1) the hub 26 is received down in the gap 40,(2) the lug 36 is received in the slot 42 between the box ribs 28, (3)the lug 38 is received in the slot 44 between the box ribs 30 and (4)the flanges 32, 34 are received in respective slots 33, 35 in the pulleybetween the box ribs. Simultaneously, it should be appreciated that thewalls of the box ribs 28, 30 are received in the channels 46 providedbetween each of the flanges 32, 34 and the lugs 36, 38.

The pulley 16 is press fit onto the end of the axle 12 and sleeve 14until the walls of the box ribs 28, 30 are fully received in thecooperating slots 49 in the reinforced collar 47. In this position, theblock-like bases 37, 39 of the respective lugs 36, 38 are fully receivedin and fill the slots 42, 44. It is the engagement of (1) the bases 37,39 in the slots 42, 44 and (2) the walls of the box ribs 28, 30 in thechannels 46 and the slots 49 in the collar 47 that keys the pulley 16 tothe axle 12 and sleeve 14 so that they are fixed and rotate together.

The radially projecting collar 47 and similar radial projections 50 atthe ends of the sleeve 14 function as barriers to prevent string, hairand other dirt and debris from contaminating and/or becoming entwined inthe drive belt and agitator bearings.

The agitator 10 of the present invention is relatively easy tomanufacture. The first step in the manufacturing process is the moldingof the nylon portion of the pulley 16 onto the metal D-nut 18. This isfollowed by the fitting of the axle 12 into the hub 26 of the pulley 16.Next is the injection molding of the sleeve 14 around the axle 12.Following injection molding is the securing of a cleaning structure suchas the tufted bristles 22 onto the sleeve 14. As noted above, this maybe accomplished by drilling an appropriate pattern of apertures in thesleeve 14 and then utilizing a friction fit and an adhesive or staplesto secure the bristles 22 in those apertures. Alternatively, dovetailchannels, grooves or other structures may be provided for receiving andholding a wiper, a brush, a beater bar or other appropriate structures.Of course, such structures may also be molded integrally with the sleeve14 when the sleeve is molded onto the axle 12 if desired.

In summary, numerous benefits result from employing the concepts of thepresent invention. The agitator 10 is made from inexpensive materials bymeans of a relatively simple and inexpensive manufacturing process.Further, the agitator 10 includes a high strength metal axle which formsa rigid spine over which relatively inexpensive plastic materials may bemolded to provide a sleeve for receiving and holding the selectedcleaning structure. Further, the overall agitator 10 may be producedwith a relatively low profile for receipt and use in low profilecleaning equipment better capable of reaching under obstructions.Advantageously, the low profile of the agitator is achieved withoutcompromising strength so that the agitator will function dependably andreliably over a long service life.

The foregoing description of the preferred embodiment of the inventionhas been presented for purposes of illustration and description. It isnot intended to be exhaustive or to limit the invention to the preciseform disclosed. Obvious modifications or variations are possible inlight of the above teachings. The embodiment was chosen and described toprovide the best illustration of the principles of the invention and itspractical application to thereby enable one of ordinary skill in the artto utilize the invention in various embodiments and with variousmodifications as are suited to the particular use contemplated. All suchmodifications and variations are within the scope of the invention asdetermined by the appended claims when interpreted in accordance withthe breadth to which they are fairly, legally and equitably entitled.

1. An agitator, comprising: a continuous metal axle; a pulley held onone end of said metal axle, said pulley including a hub secured to saidaxle and a metal D-nut engaging a stub shaft of a drive gear; a sleeveof lightweight plastic material received over said metal axle.
 2. Theagitator of claim 1, wherein said sleeve carries a cleaning structure.3. The agitator of claim 2, wherein said cleaning structure is selectedfrom a group consisting of a beater bar, a brush, tufted bristles, awiper and combinations thereof.
 4. The agitator of claim 1, wherein saidsleeve is cylindrical in shape having a diameter no greater than 22.00mm.
 5. The agitator of claim 4, wherein said axle has a diameter betweenabout 4.00 mm to about 8.00 mm.
 6. The agitator of claim 1, wherein saidpulley includes a pair of projecting box ribs and said sleeve includes apair of projecting flanges for receiving said box ribs.
 7. The agitatorof claim 6, wherein said sleeve also includes a collar and a pair ofprojecting logs for engaging in a cooperating pair of slots in said pairof box ribs.
 8. The agitator of claim 7, wherein said collar includes apair of slots for receiving said box ribs.
 9. The agitator of claim 8,wherein said pulley includes a projecting hub and said collar includes agap for receiving and holding said hub.
 10. An agitator for a vacuumcleaner, comprising: an axle; a pulley held on one end of said axle; asleeve received over said axle; and said pulley including a mountingfixture for engaging a stub shaft of a drive gear, said pulley furtherincluding a pair of projecting box ribs and said sleeve including a pairof projecting flanges for receiving and engaging said box ribs.
 11. Theagitator of claim 10, wherein said sleeve also includes a collar and apair of projecting lugs for engaging in said pair of box ribs.